GARY, Ind. (AP) -- The National Weather Service is warning people to stay out of Lake Michigan off northwestern Indiana beaches.

It has issued a beach hazards statement for dangerous swimming conditions through 7 p.m. CDT in Lake and Porter counties because waves of 3 to 5 feet, strong rip currents and strong structural currents are expected.

The weather service says dangerously pounding waves and life-threatening rip currents are expected.

Rip currents are powerful channels of water flowing quickly away from shore. They occur most often at low spots or breaks in sandbars and can sweep swimmers out into the lake.

Structural currents form along piers and break walls where long-shore currents and wave action flow into the structure. Structural currents also can sweep swimmers out into the lake.

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